Limiter
动态范围限制器
- 库:
音频工具箱 /动态范围控制
描述
这Limiterblock performs dynamic range limiting independently across each input channel. Dynamic range limiting suppresses the volume of loud sounds that cross a given threshold. The block uses specified attack and release times to achieve a smooth applied gain curve.
端口
输入
Output
Parameters
Model Examples
块特征
Data Types |
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直接进料 |
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多维信号 |
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Variable-Size Signals |
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零交叉检测 |
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算法
这Limiterblock processes a signal frame by frame and element by element.
这N-point signal,x[n], is converted to decibels:
xdB[n]passes through the gain computer. The gain computer uses the static characteristic properties of the dynamic range limiter to brickwall gain that is above the threshold.
If you specified a soft knee, the gain computer has the following static characteristic:
whereT是阈值和W是膝盖宽度。
If you specified a hard knee, the gain computer has the following static characteristic:
这computed gain,gc[n],计算为
gc[n]使用指定的攻击和发布时间参数进行平滑:
这attack time coefficient,αA,计算为
发布时间系数,αR,计算为
TA是攻击时间段,由攻击时间范围。TRis the release time period, specified by theRelease time (s)范围。FS是输入采样率,由Inherit sample rate from input或者输入样本率(Hz)范围。
如果是Make-up gain (dB)参数设置为
汽车
, the make-up gain is calculated as the negative of the computed gain for a 0 dB input:给定0 dB的稳态输入,该配置达到了0 dB的稳态输出。化妆增益取决于阈值(DB)和膝盖宽度(DB)parameters. It does not depend on the input signal.
这make-up gain,M,添加到平滑的增益中,gs[n]:
这calculated gain in dB,gm[n], is translated to a linear domain:
这output of the dynamic range limiter is given as
参考
[1] Giannoulis,Dimitrios,Michael Massberg和Joshua D. Reiss。“数字动态范围压缩机设计 - - 教程和分析。”Journal of Audio Engineering Society。卷。60,第6期,2012年,第399–408页。